New online tool predicts probability of death from stroke

Researchers at St. Michael's Hospital and the Institute for Clinical and Evaluative Sciences (ICES) in Toronto have developed a new tool that will help doctors predict the probability of death in patients after an ischemic stroke.

The study, published in the journal Circulation, found that the tool determined the likelihood of death in stroke patients 30 days and one year after an ischemic stroke. An ischemic stroke, the most common type of stroke, occurs when an artery to the brain is blocked. The tool, available online for doctors at http://www.sorcan.ca/iscore/ , is the first to use risk factors such as heart disease, diabetes, cancer and kidney disease to estimate the probability of death. The findings are being presented at the International Stroke Conference in Los Angeles.

"Doctors today have to rely on anecdotal experience to assess a patient's prognosis," says Dr. Gustavo Saposnik, a neurologist at St. Michael's Hospital and ICES scientist. "However, as doctors we tend to overestimate the likelihood of a good outcome in stroke patients. Now, with our new tool, we can accurately determine what type of outcome our patients may have, which will help guide clinical decisions."

The study examined 12,262 patients who visited an Ontario hospital from 2003 to 2008 and suffered an ischemic stroke. Using the new tool, researchers determined the death rate 30 days and one year after an ischemic stroke and compared the findings with data from the Ontario Stroke Audit to validate the results. Researchers found the tool was accurate and that risk factors including heart disease, heart failure, cancer, dementia and a history of atrial fibrillation ― an irregular heartbeat ― were associated with a higher probability of death.

"Our tool was developed and validated in the real world," Dr. Saposnik explains. "This is a tool that helps doctors estimate the risk of a poor outcome in stroke patients, helps families make more informed decisions and can be used by policymakers to accurately compare hospital performance in stroke care."